Friday, February 21, 2020

Impact of DNA damage induced by anticancer drugs on both S phase and Essay

Impact of DNA damage induced by anticancer drugs on both S phase and mitosis phase of the cell cycle - Essay Example 2005). Cells in any living organism grow, divide, perform their functions and gradually enter apoptosis (programmed cell death) at the end of their life cycle. This process is progressed through a ‘cell cycle’ which mainly consist of four stages as G1 (gap 1), S (synthesis), G2 (gap 2) and M (mitosis). Cell cycle regulation and cancer are intersected fields and hence treating cancer is more or less done in targeting the cell cycle (Collins et al. 1997). During G1, the cells grow in size and prepare for chromosome replication by synthesizing enzymes for the next stage. In S phase, the genomic DNA chromosomes are duplicated to produce two identical chromosomes (replication) and the G2 phase prepares the cells for cell division and synthesis cellular components required for mitosis in the proceeding stage. In the M phase, the replicated chromosomes are divided through a series of processes as Prophase, Prometaphase, Metaphase, Anaphase and Telophase. Subsequently the cell s plits into two identical daughter cells with cytokinensis (Lewin 1990). These cells then enter G0 (resting) stage where they carry on their respective functions or in actively dividing tissues, they once again enter G1 stage to be further divided. Each cell cycle has check points as G1/S and G2/M that is involved in correction mechanisms to prevent any error in this system. Transition through check points are signaled by cyclones and cycline-dependent kinases (CDKs). ATM (Ataxia Telangiectasia Mutated) and ATR (Ataxia Telangiectasia and Rad-3-related) protein kinases are the leading controllers in DNA damage checkpoint signaling (Nishida et el. 2009). This mechanism ensures any error during DNA synthesis mechanism does not pass through the cell cycle. Cells with any mistake are either repaired before progressing or enter into apoptosis (programmed cell death) if the errors cannot be rectified. The G1/S check point ensures the cells have grown into the appropriate size and the DNA is not damaged while in the G2/M check point it is confirmed that the DNA is properly replicated during the S phase. Another check point in the M stage (metaphase check point), see that the chromosomes are properly aligned on the spindle at metaphase. Any mistake detected in any of these check points force the cells to repair or enter apoptosis. Chemotherapy is an efficient and a widely used method of treating cancer. Here the cancerous cells are treated with anticancer/antineoplastic drugs and apoptosis is induced (Muller et al. 1999). Usually a combination of two or more drugs is administered to the patient to increase efficiency. Chemotherapeutic treatments are targeted to destroy actively proliferating cells since cancerous cells are highly proliferating. This has the disadvantage of attacking rapidly dividing normal cells such as in the bone marrow, intestine and hair follicles and cause chemotherapy side effects as hair loss (alopecia) and inflammation in the digestive tract (mu cositis) since the anticancer drugs fails to identify cancerous and normal cells but simply destroys the fast proliferating cells. Chemotherapeutic agents or anticancer drugs are mainly aimed toward cell cycle at

Wednesday, February 5, 2020

Company Introduction, Market Segmentation, and Product Repositioning Research Paper

Company Introduction, Market Segmentation, and Product Repositioning - Research Paper Example Strategic Mission Statement The mission of Holden Trucking Services is to be preferred trucking firm by being able to deliver the most affordable, high quality and efficient trucking services to the customers. According to Radhakrishnan (2001), trucking services form a very important part of the supply chain for many business and it is critical that it is efficient in terms of service as well as cost. This is what Holden Trucking Services will seek to be doing, that is, provide efficient and reliable services to customers at affordable prices. In its growth outlook, Holden Trucking Services looks to serve the African market. The African market is the most underserved market in this sector of the global economy. Africa is expected to be next big economy in the next twenty years. According to market experts, the current fast growing markets such as India and China will have reached their optimum growth by the year 2050. At the current moment, every firm including trucking firms are con centrating their foreign market growth in the BRICS market. As the African market is being ignored, it is going to be easy for Holden Trucking Services to establish itself as the trucking firm of choice and be able to take advantage when the opportune e time comes. The African market is already a ripe market and is underserved and even without having to wait for the opportunities time. Most African countries don’t have dependable trucking services of their own and therefore depend on foreign firms. None of these foreign firms have been gracious enough to offer localised trucking services. This means that the services are too expensive for the local African market. The services are also inefficient and not dependable especially where time of delivery is critical. Holden Trucking Services will be the trucking firm to fill this gap to make sure that the local market is well served. Marketing Plan Holden Trucking Services will reach the market by personalising the services. The m arket will be divided into smaller cells with each cell being given as much autonomy as possible. This will make sure that every area can be served individually and this will increase the quality of the service to the customers. Holden Trucking Services will also seek to be a low-price leader. The modern trucking business is too expensive for most customers an this always has a negative implication of the customers because most of the customers are businesses which would benefit a lot if they could find a cheaper way to deliver their goods so that they can expand their profit margins (Kendall, 2005). Offering low prices and high quality of service to the customer will be an easy way to enter in the market and Holden Trucking Services seeks to use this as a way to make sure that it curves a market share for itself. Segmentation of the Market Holden Trucking Services will seek to serve the underserved market. Such underserved market include the small scale businesses which usually can not afford to have their own trucks but at the same time find trucking services prohibitively high. In this regard, to be able to serve this market, Holden Trucking Services will use two main strategies. First, it will include smaller trucks rather than having only large trucks. These smaller trucks will help in making sure that the firm is able to dispatch customer’